Air quality modelling to support Runnymede`s Local Plan
Runnymede Borough Council is preparing a Local Plan to guide development in Runnymede in Surrey, south west of London. The CERC Consultancy team carried out air dispersion modelling using ADMS-Urban to identify the baseline air quality profile across the area and to assess air quality for future scenarios (2030 and 2036), with and without developments associated with the Local Plan in place.
The main source of air pollution in Runnymede is road traffic emissions. The Council has declared two Air Quality Management Areas (AQMAs) due to annual average NO2 concentrations exceeding the Air Quality Objective: along the M25 and in Addlestone town centre.
Modelling for the base year, 2015, showed exceedences of the annual average NO2 Air Quality Objective (AQO) along the M25 and at building façades in Chertsey. In the modelled future scenarios, no exceedences of the AQOs were calculated. This reflects the expected large reduction in NO2 concentrations due to improvements in engine technology, which lead to a fall in traffic exhaust emissions.
The health impact of air quality on health in Runnymede was assessed by calculating the number of attributable deaths and corresponding life-years lost due to concentrations of PM2.5 and NO2. The difference in life years lost with and without the Local Plan in place was very small, reflecting the low concentrations predicted across the Borough.